title: Catalyst-controlled divergent C-H functionalization of unsymmetrical 2-aryl cyclic 1,3-dicarbonyl compounds with alkynes and alkenes.
abstract: Achieving site-selective, switchable C-H functionalizations of substrates that contain several different types of reactive C-H bonds is an attractive objective to enable the generation of different products from the same starting materials. Herein, we demonstrate the divergent C-H functionalization of unsymmetrical 2-aryl cyclic 1,3-dicarbonyl compounds that contain two distinct, nonadjacent sites for initial C-H functionalization, where product selectivity is achieved through catalyst control. By use of a palladium-N-heterocyclic carbene complex as the precatalyst, these substrates undergo oxidative annulation with alkynes to provide spiroindenes exclusively. In contrast, a ruthenium-based catalyst system gives benzopyrans as the major products. Examples of divergent, oxidative C-H alkenylations of the same substrates are also provided.
authors.affiliation: EaStCHEM, School of Chemistry, University of Edinburgh, Joseph Black Building, The King's Buildings, West Mains Road, Edinburgh, EH9 3JJ, United Kingdom.
authors.forename: Johnathon D
authors.initials: JD
authors.lastname: Dooley
authors.forename: Suresh
authors.initials: S
authors.lastname: Reddy Chidipudi
authors.forename: Hon Wai
authors.initials: HW
authors.lastname: Lam